Half-Sandwich Alkyl, Amido, and Iodo Samarium(II) Complexes: Non-Conventional Sterically Governed Oxidation of (tBu4Carb)2Sm
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- 作者：Alexander N. Selikhov ; Tatyana V. Mahrova ; Anton V. Cherkasov ; Prof. Dr. Georgy K. Fukin ; Dr. Laurent Maron and Prof. Dr. Alexander A. Trifonov
- 刊名：Chemistry - A European Journal
- 出版年：2017
- 出版时间：January 26, 2017
- 年：2017
- 卷：23
- 期：6
- 页码：1436-1443
- 全文大小：890K
- ISSN：1521-3765
文摘
The half-sandwich tetra-tert-butylcarbazol-9-yl iodo complex [(tBu4Carb)Sm(μ-I)(THF)2]2 (1) was synthesized by the salt metathesis reaction of tBu4CarbK and SmI2(THF)2 in THF. Complex 1 along with metallic Cu was also isolated from the oxidation reaction of (tBu4Carb)2Sm by CuI. The formation of stable radical tBu4Carb. was detected in this non-conventional process, indicating preferential oxidation of anion tBu4Carb− vs. SmII. The treatment of 1 with two equivalents of dibenzo-18-crown-6 resulted in heterolytic dissociation of a η5-bond Sm-tBu4Carb and afforded an ionic compound [tBu4carb−][SmI(crown)(THF)2]+ (4). Alkylation of 1 with o-NMe2C6H4CH2K (1:2 molar ratio) in THF allowed for the synthesis of half-sandwich SmII alkyl complex (tBu4Carb)SmCH2(o-NMe2C6H4CH2)(THF)2 (5) in 55 % yield. The amido complex (tBu4Carb)SmN(SiMe3)2(DME) (6) was obtained by the reaction of 1 with two molar equivalents of NaN(SiMe3)2 in THF in 89 % yield.